1. Technical Field
Example embodiments of the inventive concept relate in general to wireless local area network (WLAN) technology, and more specifically, to technology of allocating a channel in an overlapping basic service set (OBSS).
2. Related Art
Various wireless communication technologies are being developed along with the development of information communication technology. Among them, wireless local area network (WLAN) technology is technology to allow a mobile terminal such as a personal digital assistant (PDA), a laptop computer, a portable multimedia player, a smart phone, a tablet personal computer (PC), etc. to connect to the Internet wirelessly in homes and businesses, or a specific service provision area based on radio frequency technology.
A standard of the WLAN technology is being developed as an Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard. The WLAN technology according to an IEEE 802.11a standard operates based on an orthogonal frequency division multiplexing (OFDM) method, and provides a transmission speed of maximum 54 Mbps in a 5 band GHz. The WLAN technology according to an IEEE 802.11b standard operates based on a direct sequence spread spectrum (DSSS) method, and provides a transmission speed of maximum 11 Mbps in a 2.4 GHz band. The WLAN technology according to an IEEE 802.11g standard operates based on the OFDM method or the DSSS method, and provides a transmission speed of maximum 54 Mbps in the 2.4 GHz band.
The WLAN technology according to an IEEE 802.11n standard operates in the 2.4 GHz and 5 GHz bands based on the OFDM method, and when using a multiple input multiple output-OFDM (MIMO-OFDM) method, provides a transmission speed of maximum 300 Mbps with respect to four spatial streams. The WLAN technology according to the IEEE 802.11a standard supports a maximum channel bandwidth of 40 MHz, and in this case, provides a transmission speed of maximum 600 Mbps.
As the spread of the WLAN is ongoing and various applications using the same are developed, there is an increasing need for a new WLAN to support a greater throughput than a data processing speed which the IEEE 802.11n standard supports. Very high throughput (VHT) WLAN technology is one of the IEEE 802.11 technologies which are being offered in order to support a data processing speed which is equal to or more than 1 Gbps. Among them, an IEEE 802.11ac is being developed as a standard for providing the VHT at a band which is equal to or less than 5 GHz, and an IEEE 802.11ad is being developed as a standard for providing the VHT at a 60 GHz band.
As use of the WLAN has recently increased, a possibility of using an overlapping channel between adjacent access points (or, adjacent basic service sets (BSSs)) has been increased. Since the overlapping channel between the adjacent access points is used, there is a problem in that performance of the WLAN degrades.